Liquid and solid fuel furnace.



G. R. GREGORY.

LIQUID AND SOLID FUEL FURNACE.

APPuc/mou FILED Nov. 19, 1910.

1 1 37, 3 1 O. Patented Apr. 27, 1915.

2 SHEETS-SHEET l- L z' 2165595 M THE NORRIS PETERS C0., PHOT0-LITHO., WASHINGTON, D 4

G. R. GREGORY.

LIQUID AND SOLID FUEL FURNACE.

APPLlcATIoN FILED Nov.19, 1910.

1 1 37,3 1 O, Patented Apr. 27, 1915.

2 SHEETS-SHEET 2.

THE MORRIS PETERS 50,. PHOID-LITHO.. wAsHlNcwN. D4 c.

GEORGE ROBERT GREGORY, OF W'ESTD/IINSTEE,

LONDON, ENGLAND.

LIQUID AND SOLD FUEL FURNACE.

Specifrcation cf Letters Patent.

Patented Apr. 27, 1915.

Application filed November 19, 1910. Serial NoA 593,253.

T0 all 10h/)mit may concern Be it known that 1, GEORGE ROBERT 'i l va t 11u-iconic, a subject of the lering of Great Britain and Ireland, residing at la' estminster, in the county of London, England, have invented improvements in Liquid and Solid Fuel Furnaces, of which the following is a specification.

According to this invention gases from a retort or generator located at or near the level of fuel on the grate of a furnace, for example as described in the specication of prior British Letters Patent No. 12372A of 1906, are led therefrom by pipes into an ejector casing located above the lire grate, and steam or compressed air is delivered into such casing by a nozzle, tapering it may be toward its outlet, the arrangement being such that the jet of steam or compressed air passing through the ejector casing creates a partial vacuum and causes the gases to flow through a suitably arranged discharge pipe in communication with an air heating chamber that can conveniently embrace the furnace doorway as for eX- ample in the apparatus described in the said prior specification, the gases as they flow through the discharge pipe meeting and mixing with the heated air coming from the air heating chamber before entering the combustion space above the fuel. The ejec tor casing is or can be formed with tubular branches into which the gas pipes from the retort or generator are fitted. For enabling the furnace to be worked at will with or without liquid fuel as described an air inlet opening can be formed in the underside of the retort near its outer end and a door, usually sliding, can be provided whereby the opening can be readily closed in an air tight manner when liquid fuel is being supplied to the retort and be easily opened when not so using such fuel.

The accompanying drawings illustrate the application of this invention to a marine boiler furnace, Figure 1 being a longitudinal vertical section, Fig. 2 a section just above the dead plate, Fig. 3 a front elevation; and Fig. 4 a front elevation with the furnace front removed. Fig. 5 is a detail section illustrating a modification.

a is a retort or generator arranged centrally atthe level of the grate b and extending from the front of the furnace into a transverse chamber c which forms part of the bridge and is provided with laterally arranged return passages cZ that communicate with the casing e of an ejector' and are connected to tubular branches el of the casing, as shown in Fig. 4, by curved pipes The ejector is arranged within an air heating chamber g around the fire door opening and terminates just within the discharge pipe '(71 above the grate. This ejector is shown with a steam nozzle h, but compressed air may be used instead of steam, and, in some cases, it may be desirable to fit the nozzle with an additional cone as shown at h1 Fig. 5. Some of the gases enter the rear end of the cone h1 and are induced by the steam or compressed air to iow through same thus tending to produce a more complete mixture of the gases and the steam or compressed air. The front end of the retort or generator a is fitted with an injector' t' which is connected to a steam supply pipe j controlled b v a cock jl and to a liquid fuel supply pipe c. 1n order to facilitate a proper regulation of the supply of liquid fuel when beine supplied to the retort or generator, an air tight sight feed device Z is fitted in the liquid fuel supplv pipe 7c and a controlling valve m at the inlet end of such derice is provided with a dial n graduated to indicate the rate of supply, the handle of the controlling valve being arranged to work over said dial.

0 is an opening in the underside of the retort o through which, when the liquid fuel supply thereto is cut off. air is drawn by the iet of steam issuing from the iniector c', the mixture of steam and air being forced through the retort a, chamber c and passages d to the pipes f and ejector casing e where it arrives in a highlv heated condition. When liquid fuel is supplied to the retort a the opening o is closed by a door J77. Steam or compressed air from the nozzle h delivers the mixture into the discharge pipe g1 where it mixes with heated air from the chamber g.

Air inlets o to the air heating chamber g are furnished with doors r whereby any required regulation of the air supply can be made. Air may be supplied to the solid fuel burning on the furnace dead plate s through holes t formed through that portion of the dead plate forming the base of the furnace doorway.

For the purpose of enabling a supply of air to be delivered into the combustion chamber at the backof the fire grate the bridge is formed With a passage u leading upwardly and rearwardly to the combustion chamber 0 at the rear of the bridge from a chamber u1 into Which air from the space belov.vv the fire grate can be allowed to pass through an opening a controlled by a Valve or damper '1,'. rlhe upper or exit end of the air passage is so located as not to become choked by ashes falling over the baclr of the fire bridge; for example, the upper rear part of the fire bridge can project slightly beyond the exit end of the passage as shown. The valve controlling the supply of air to the air passage of the fire bridge is, in the construction illustrated, in the form of a hinged plate and is operated by a rod 2 pivoted thereto and extended to the front end of the furnace Where it terminates in a handle adjacent to which the underside of the rod is formed with grooves or recesses any one of which is adapted to engage a fixed holding tooth or rail.

As will be understood the precise details of construction will depend upon the particular applications.

Vhat I claim is 1. The combination, in a liquid and solid fuel furnace, of a grate, a retort near the level of the grate, means adapted t0 inject liquid fuel into the retort, an air heating chamber at the front of the furnace having a controllable inlet and discharge pipe directed over the grate toward the rear of the furnace so that the draft of the furnace tends to draw air from such chamber, an ejector located in said chamber and adapt-ed to discharge into the discharge pipe of such chamber, means adapted to supply fluid under pressure to the ,ejector and a connector placing the ejector in communication With the retort so that the fluid under pressure and gas are caused to issue in a Well mixed jet into the discharge pipe of the air heating chamber, the arrangement being such that the hot air introduced into the furnace is controlled in part by the draft of the furnace and in part by the mixed jet of gas and fluid supplied independently under pressure to the ejector.

2. In a liquid and solid fuel furnace, the combination with a grate, of a retort near the level of the grate, means for injecting liquid fuel into the retort and cutting off the supply at will. an air inlet and means controlling the same whereby air may be drawn into the retort when the liquid fuel supply is cut off, an air heating chamber at the front of the furnace having a controllable inlet and a discharge pipe directed over the grate toward the rear of the furnace so that the draft of the furnace tends to draw air from said chamber, an ejector located in said air heating chamber and having its discharge directed into the discharge from said air heating chamber, means for supplying i'luid under pressure to said ejector, and suitable connections whereby the ejector is placed in communication with the retort so that the fluid under pressure and gas are delivered in a Well mixed jet into the discharge from the air heating chamber, the hot air introduced into the furnace being controlled in part by the draft of the furnace and in part by the mixed jet of fluid and gas supplied under pressure to the ejector.

3. In a liquid and solid fuel furnace, the combination with a grate, of a retort near the level of the grate, liquid fuel injecting means and an associated steam jet for introducing commingled liquid fuel and steam into said retort, au ejector located above the grate and in communication with said retort through return passages therefrom for forcing air or steam into the combustion chamber, an air heating chamber inclosing said ejector and having a discharge pipe in front of thel delivery end of said ejector directed over the grate and in communication with said air heating chamber, an air inlet to said retort, means for controlling said air inlet, and means for shutting off the supply of liquid fuel to the retort.

el. In' a liquid and solid fuel furnace, the combination with a grate, of a retort near the level of the grate, liquid fuel injecting means and an associated steam jet for intro ducing commingled liquid fuel and steam into said retort, an ejector located above the grate and in communication with said retort through return passages therefrom for forcing air or steam into the combustion chamber, an air heating chamber inclosing said ejector and having a discharge pipe in front of the delivery end of said ejector directed over the grate and in communication with said air heating chamber, an air inlet to said retort, means for controlling said air inlet, and independent means for shutting off the supply of liquid fuel and steam to said retort.

Signed at London England this v7th day of November 1910.

GEoRGE RoRERT GREGORY.

Witnesses:

VVAME KNAPTON, HERBERT D. JAMESON.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

